Copper alloys



lit

Patented Nova 22, 1938 UNITED STATES PATENT OFFICE corrna more Franz R.Hensel and Earl I. Larsen, Indianapolis,

Ind.,

'assignors to P.-R.. Mallory & Co., Inc.,

" Indianapolis, Ind., a corporation of Delaware No Drawing. ApplicationAugust 12, 1938, Serial No. 224,499

1 Claim.

This invention relates to copper alloys. This case is a continuation inpart of our copending application S. N. 164,032, filed September I isdescribed herein, it is contemplated that con-.

siderable variation may be made in the method of procedure and thecombination of elements,

vgithout departing from the spirit of the invent on.

The present invention relates to the improvement of alloys of copper andzirconium. Ascording to the present invention the improved alloys aremade of the following elements in substantially the followingproportions;

I Per cent Metal selected from the group consisting of iron, cobalt andnickel 0. 1 to 30 Zirconium 0. 05 to 5 Beryllium 0. 05 to 3 Copperbalance Where high electricalconductivities are desired, it is preferredto keep the proportion of iron 7 group metal within an upper limit of5%.-

, The alloys of the present invention may also contain smallproportions,or even up to several percent, of zinc, tin, calcium, lithium,magnesium, phosphorus and silver. I f

The beryllium combines with theiroh group metal or metals to form theberyllide"th'er'eof and thereby imparts age-hardening characteristics tothe alloy.

The addition of zirconium in this type of alloy not only impartsadditional age-hardening characteristics, but alsoproduces a material ofcorrosion resistance, hgh strength at elevated'temperatures and superiorfatigue and impact properties. I i- The-alloys can be made according tostandard alloying methods. A preferred method for introducing thezirconium is to prepare a hardener alloy containing a high percentageoi. zirconium and then introduce a'predetermined amount of this alloyinto a coppermelt, containing the other ingredients in the desiredproportions.

After the alloy has been prepared according tosuch methods, the materialmay be heat 5 treated by firstquenching the'alloy in the form of abillet or sand casting, or any other form,

, from above 700 C. and subsequently aging at a temperature below 700 C.In certain cases, we have found it also advisable to use one heat 10treatment only, namely, the low temperature treatment, and eliminate thequenching treatment. 4 I

If the materials are processed by rolling, extruding, drawing, forgingor any other fabricatl5 ing methods, we have found it desirable in manycases to quench the materials from the intermediate anneals, coldworking same and applying an aging treatment afterwards. This coldworking before aging hastens considerably the pre- 20' cipitation ofthedispersed phase. In addition, a certain amount of cold work may beapplied after aging in order to improve the surface finish of thewrought material.

An example of an alloy produced according to 25 the present inventionis:

Per cent Zirconium 0.. 6'! Cobalt- 2.04: Silico 0.83 at: Copper balanceAfter quenching this alloy from 950 C. and aging at 450 0., a Rockwell Bhardness of was .obtained,,with an excess of 45% electrical con- 35strips, or tubing.

The composition which has exceptional merits for condenser tubing is asfollows: its

. Per cent Nickel 15 to 30 Zirc n 0. 05 to 5 Beryllium 0. 05 to 3 Copperbalance 5 'While the present invention as to its objects and advantageshas been described herein as carried out, in specific embodiments, it isnot desired to be limited thereby, but it is intended to 55 cover theinvention broadly within the appended lium, and the balancesubstantially all copper, clalm. characterized by high hardness andfurther char- What is claimed is: acterized by the fact that itshardness is not per- A heat-treated alloy composed of 0.05 to 5%manently adversely affected by temperatures in o zirconium, 0.1 to 30%of a metal or a combinathe order of 450 C. tlon of metals selected fromthe group consist- FRANZ R. HENSEL. in: of iron, cobalt and nickel, 0.05to 3% beryl- EARL I. LARSEN.

